Most valuable US stamps: documented rarities and prices

What makes a US stamp worth a fortune, and why yours probably is not

A US stamp reaches six or seven figures when three things line up: very few copies exist, those copies can be told apart from the common ones, and collectors can follow each copy's history. The stamps below pass that test. Most old US stamps pass none of it.

Every price in this guide is a dated, reported result for one named specimen. None of them is the worth of a stamp that merely looks similar. The common stamp beside each rarity usually sells for dollars, not thousands, and that gap is the point of the list.

Each section gives the mark that identifies the rarity, one documented price with its label, and the lookalike that fools people. Where the site has a dedicated guide, it is linked.

The documented cases at a glance

A hammer price is the winning bid. A total price adds the buyer's premium. The last column says which one each figure is, as far as the source states it. Several results are old, and they are history, not current appraisals.

1c Z grill (1868): the most valuable US stamp

The one-cent Z grill is a blue Franklin stamp from 1868. The back carries a grid of tiny points whose ridges run horizontally. Siegel sold the copy from the Bill Gross collection on June 14, 2024 for $4,366,000, and describes it as the only one-cent Z grill available to collectors.[1] Mystic Stamp Company, which had bought the same stamp in 1998 for $935,000, called it the most valuable US stamp again.[2]

You cannot see a Z grill from the front, and the common E grill looks almost identical. The Z grill identification guide shows how to tell them apart by ridge direction and compares dealer asking prices for Z, E and F grills.

24c Inverted Jenny (1918): one sheet of 100

The 24-cent airmail stamp of May 1918 was printed in two colors, a red frame and a blue Curtiss JN-4 biplane. On one sheet the plane printed upside down. William T. Robey bought that sheet at a Washington post office on May 14, 1918, and it is the only sheet of inverts sold by the Post Office, so only 100 exist.[5][23] Robey sold the sheet to the dealer Eugene Klein for $15,000.[6]

Position 49, a never-hinged copy that the Philatelic Foundation graded 95, realized $2,006,000 at Siegel on November 8, 2023. A report at the time called it a record for a single United States stamp.[3][22] Position 69 has original gum but was previously hinged. It realized $495,600 at Siegel on June 14, 2024.[4] Gum and condition move the price as much as the error itself.

How to spot an Inverted Jenny and its lookalikes

Look for a blue plane flying upside down inside a red frame, with perforations on all four sides. Because only 100 exist, each is tracked by position on the sheet. When a long lost copy resurfaced, the Philatelic Foundation matched it to its position from earlier records.[6] A claimed new find deserves doubt.

Fakes and wishful identifications exist. An Iowa museum displayed what it believed was an Inverted Jenny for about 20 years, and experts later said it was a fake.[7]

The normal Jenny is a common stamp. On October 29, 2026, Mystic asked $85.00 for a used single and $165.00 for a mint one, with a used stamp with small flaws at $49.00.[8] The Curtiss Jenny stamp guide covers the normal issue.

5c Alexandria Blue Boy (1847): a cover, not a loose stamp

Local postmasters issued their own stamps between 1845 and 1847, before national stamps took over. Seven Alexandria, Virginia provisionals are known, and six are on buff paper. Only one is on blue paper. That is the Blue Boy, and it stays attached to its original envelope.[11]

David Feldman sold the cover by tender for $1,000,000 on May 8, 1981.[10] H.R. Harmer sold it on June 22, 2019 for $1.18 million, which included an 18 percent commission on a $1,000,000 bid. The sale report adds that the cover has been restored, with sealed tears.[9]

The lesson for a collection is practical. A provisional is judged by type, paper and whether it still sits on its cover, so never lift an old stamp off a cover to see it better.

1869 Pictorial inverts: the 15c and 24c

The 1869 pictorials were the first US stamps printed in two colors. The frame and the center picture came from separate plates, and a sheet fed upside down for the second pass gave an inverted center.[13] Inverts exist on the 15c, 24c and 30c. Siegel's census counts about 100 of the 15c invert, with one copy having gum, two unused without gum and 97 used.[12]

The unused ones are the six-figure stamps. In February 2008, Philip Weiss Auctions sold an unused, no-gum 24c invert, one of four unused known, for $1.27 million. An unused 15c invert, one of three, was reported at $757,100 hammer.[14] A used copy is a different object. At Siegel on October 10, 2013, a used 24c invert with a small corner crease made $26,000 and a used 15c with a star cancel made $10,500.[15] Those reports do not say whether buyer's premium was included, and both sales are years old.

Check the picture against the frame. The 15c center shows the Landing of Columbus and the 24c center shows the signing of the Declaration of Independence. On the error the scene is upside down while the frame lettering reads normally. A normal 1869 stamp with shifted perforations is not an invert, and the stamp errors and varieties guide explains the common errors.

1901 Pan-American inverts: the 1c, 2c and 4c

The Pan-American Exposition set of 1901 has three inverted-center stamps. The 1c and 2c reached post offices by accident. The 4c invert was printed on purpose after a misunderstanding and never went on sale. The Bureau of Engraving and Printing sent 400 copies to a Post Office official, who gave 172 away.[18][24]

At Siegel on October 6, 2016, a 1c invert graded extremely fine 90 realized $51,750 and a 4c graded extremely fine 90 realized $120,750, both reported as totals.[17] Paul Fraser reported the finest known 2c invert, one of 64 known singles, at $170,000 and the 4c at $105,000 from the same sale.[16] The 4c figure is lower than the Linn's total, which suggests Paul Fraser quoted hammer prices. That is an inference, not a statement from either source.

A 2001 souvenir sheet reproduced the three inverts, as the Smithsonian notes.[18] An upside-down scene on a modern keepsake is not a 1901 error. Check the date and the format. The Pan-American Exposition stamp guide covers the normal set.

The famous invert that sells for cents: Dag Hammarskjöld, 1962

Not every invert is rare. After an inverted-background error turned up on the 4c Dag Hammarskjöld stamp of October 23, 1962, the Post Office Department reprinted about 40 million of them on purpose so the error could not become a rarity.[19] On October 29, 2026, Mystic asked $0.40 for a mint single and $0.50 for a used single of the inverted stamp, Scott 1204.[20]

An upside-down or shifted color on a modern stamp is rarely a find. Look up the exact catalog number and the quantity printed before you get excited.

Hammer price, total price, catalog value: read the label

Auction houses add a buyer's premium to the winning bid. Harmer's 2019 Blue Boy total of $1.18 million was an 18 percent commission on a $1,000,000 bid.[9] The Society of Inverted Jenny Owners lists a catalog value beside each realized price, and the two can differ widely: Position 49 carried $850,000 against $2,006,000 realized.[3]

Catalog value is a publisher's estimate, not a sale. A dealer's asking price is what a seller wants, not what anyone paid. Never average these numbers, and never compare a unique cover with a single stamp or an unused stamp with a used one.

How to check an old US stamp against this list

Work from the stamp in your hand toward the list, not the other way around. These steps take a few minutes and cost nothing.

• Read the denomination, design and year first. Each stamp above is one exact issue: the 1c Franklin of 1868, the 24c airmail of 1918, the 5c Alexandria provisional, the 15c or 24c of 1869, or the 1c, 2c or 4c of 1901.
• Compare the picture with the frame. On the 1869 and 1901 inverts the center scene is upside down. If the picture is only off-center, it is a common shifted-center stamp.
• For an 1867-68 US stamp, examine the back for a grill and follow the ridge-direction test in the Z grill guide.
• Find the Scott number with the [catalog number guide](/blog/find-stamp-catalog-number). Invert numbers carry a letter suffix, for example 294a, 119b, 120b and C3a.
• Photograph both sides in even light. The [identify a stamp from a photo guide](/blog/identify-postage-stamp-from-photo) explains how.
• Do not clean, hinge or tear a stamp from its envelope.

Where an ordinary old US stamp sits instead

Most inherited US stamps are common issues. Mystic's October 29, 2026 asking prices for the normal 24c Curtiss Jenny, the same design as the rarity above, were $49.00 for a used stamp with small flaws, $85.00 for a used single and $240.00 for a fine, never-hinged mint stamp.[8] That is a real price for a real stamp, and the $2,006,000 Position 49 result is more than 20,000 times the used single.

To compare ordinary issues, use the old stamps price list and the guide on how much your old stamp is worth. For famous cases outside the United States, read most valuable stamps by country.

When to stop and ask an expertizing service

If a stamp matches one of the descriptions above, stop handling it. Put it in a stamp-safe sleeve, photograph both sides, and ask a recognized service such as the [Philatelic Foundation](https://www.philatelicfoundation.org/) for an opinion.[21] A written opinion, not a phone photo or an app result, is what a serious buyer will ask to see.

Fakes and reproductions of famous rarities exist.[7][18] Before selling anything, search the stamp's exact catalog number in auction archives and treat dealer asking prices as asks.

Frequently asked questions